In areas where one would need to winterize a water system having a water heat exchanger, there is a need to prevent the winterizing fluid from entering the water heat exchanger. Once the water heat exchanger is drained, the risk of harm due to freezing is minimized. However, the lines that carry water or other fluids should be filled with a fluid that prevents freezing. Thus, there is a need for a bypass system.
In vehicles that move, there is a need for a better system, as almost all systems currently in use employ custom bypasses that are typically custom for each application. During construction, of say for example a recreational vehicle (RV), a system of numerous hoses and valves is built on site on an individual basis. During the construction of RVs, this is done in the assembly area.
It must be understood that in the assembly area, there is a lot of particulate from all of the cutting and other construction activities. Debris in any of the lines, valves or clamps can cause failure of the seal in any of the valves. If a valve is compromised, the entire fabrication of the by-pass system must be redone. For each line, valve and clamp that is used, the changes of failure increase by a factor.
Additionally, the bypass system of the prior art, due to its complicated nature and individual builds, requires increased manpower to construct.
Given that valve failure is the primary reason the bypass system has to be replaced, the number of valves in the bypass system of the prior art makes it very difficult to identify the location of the failure. Additionally, the number of valves increases the chances of failure. Also replacement in the field is made more complicated by the fabrication of the bypass of the prior art.
The current invention uses two bypass/three-way valves. The prior art on at least three separate occasions teaches that only one three-way valve and one check valve can be used. In U.S. Pat. No. 7,954,506 to Swan states a “check valve 51 is installed between the water heat exchanger out water outlet 53 and the bypass valve 38 to prevent backflow into the water heat exchanger discharge from the bypass valve.” (Col 2., lines—32-35) U.S. Pat. No. 4,286,617 states that “in the normal water supply state, when hot water is in the hot water heat exchanger, it causes a slightly higher pressure thus making valve 20′ seal leak slightly because of the back pressure from hot water heat exchanger. This is the reason for the check valve 46.” U.S. Pat. No. 7,762,280 states that the “internal bypass port 208 . . . is not preferred when elastomeric seals are used since the seal will not be maintained uniformly compressed when the valve is in the bypass position which could result in premature failure or increased friction. (Col. 4, line 60-Col. 5, line 4) It is clear that the art uses check valves between the water heat exchanger and the three-way valve or does not use a three-way valve at all.